问题描述
我需要使用一个数据库进行查询(非修改)和一个用于命令(修改).我使用的是 Spring Data JPA,所以我有两个配置类:
I need to use one database for queries (non-modifying) and one for commands (modifying). I am using Spring Data JPA, so I have two configuration classes:
@Configuration @EnableJpaRepositories(value = "com.company.read", entityManagerFactoryRef = "readingEntityManagerFactory", transactionManagerRef = "readingTransactionManager") @EnableTransactionManagement public class SpringDataJpaReadingConfiguration { @Bean(name = "readingEntityManagerFactory") public EntityManagerFactory readingEntityManagerFactory() { return Persistence.createEntityManagerFactory("persistence.reading"); } @Bean(name = "readingExceptionTranslator") public HibernateExceptionTranslator readingHibernateExceptionTranslator() { return new HibernateExceptionTranslator(); } @Bean(name = "readingTransactionManager") public JpaTransactionManager readingTransactionManager() { return new JpaTransactionManager(); } } @Configuration @EnableJpaRepositories(value = "com.company.write", entityManagerFactoryRef = "writingEntityManagerFactory", transactionManagerRef = "writingTransactionManager") @EnableTransactionManagement public class SpringDataJpaWritingConfiguration { @Bean(name = "writingEntityManagerFactory") public EntityManagerFactory writingEntityManagerFactory() { return Persistence.createEntityManagerFactory("persistence.writing"); } @Bean(name = "writingExceptionTranslator") public HibernateExceptionTranslator writingHibernateExceptionTranslator() { return new HibernateExceptionTranslator(); } @Bean(name = "writingTransactionManager") public JpaTransactionManager writingTransactionManager() { return new JpaTransactionManager(); } }
在我的存储库中,我有时需要使用 EntityManager 来决定这样使用:
In my repository I sometimes need to decide with EntityManager to use like so:
@Repository public class UserReadingRepository { @PersistenceContext(unitName = "persistence.reading") private EntityManager em; // some useful queries here }
我正在使用 persistence.xml 中定义的持久性单元名称:
I am using persistence unit's name as defined in my persistence.xml:
<persistence xmlns="http://www.51sjk.com/Upload/Articles/1/0/336/336201_20221104102808798.jpg" xmlns:xsi="http://www.51sjk.com/Upload/Articles/1/0/336/336201_20221104102809579.jpg" xsi:schemaLocation="http://www.51sjk.com/Upload/Articles/1/0/336/336201_20221104102808798.jpg http://www.51sjk.com/Upload/Articles/1/0/336/336201_20221104102808798.jpg/persistence_2_0.xsd" version="2.0"> <persistence-unit name="persistence.reading" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider> <non-jta-data-source>ReadingDS</non-jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" /> <property name="hibernate.show_sql" value="true" /> </properties> </persistence-unit> <persistence-unit name="persistence.writing" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider> <non-jta-data-source>WritingDS</non-jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" /> <property name="hibernate.show_sql" value="true" /> </properties> </persistence-unit> </persistence>
Spring 抛出 org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'persistence.reading' 被定义.奇怪的是,Spring 似乎试图用持久性单元名称实例化 a bean?我是不是配置错了什么?
Spring throws org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'persistence.reading' is defined. Oddly, it looks like Spring tries to instantiate a bean with persistence unit name? Did I misconfigure something?
UPDATE:当我从 @PersistenceContext 注释中删除 unitName = "persistence.reading" 时,我会收到以下错误:org.springframework.beans.factory.NoUniqueBeanDefinitionException:没有定义 [javax.persistence.EntityManagerFactory] ??类型的合格 bean:预期的单个匹配 bean 但找到了 2:readingEntityManagerFactory,writingEntityManagerFactory
UPDATE: When I remove unitName = "persistence.reading" from @PersistenceContext annotation, I will get following error instead: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: readingEntityManagerFactory,writingEntityManagerFactory
更新 2:Rohit 建议(在评论中)改为连接 EntityManagerFactory.所以我尝试执行以下操作:
UPDATE 2: Rohit suggested (in the comment) to wire EntityManagerFactory instead. So I tried to do the following:
@PersistenceUnit(unitName = "persistence.reading") private EntityManagerFactory emf;
但 Spring 只报告:org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'persistence.reading' is defined
but Spring only reports: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'persistence.reading' is defined
最终修复:感谢 Vlad 的回答,我能够更新代码以使用以下内容(只需确保您也定义了 dataSource bean):
FINAL FIX: Thanks to Vlad's answer, I was able to update the code to use the following (just make sure you define your dataSource bean as well):
@Bean(name = "readingEntityManagerFactory") public EntityManagerFactory readingEntityManagerFactory() { LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean(); em.setPersistenceUnitName("persistence.reading"); em.setDataSource(dataSource()); em.setPackagesToScan("com.company"); em.setJpaVendorAdapter(new HibernateJpaVendorAdapter()); em.afterPropertiesSet(); return em.getObject(); }
推荐答案
EntityManageFactory 配置不正确.您应该使用 LocalContainerEntityManagerFactoryBean 代替:
The EntityManageFactory is not properly configured. You should use a LocalContainerEntityManagerFactoryBean instead:
@Bean(name = "readingEntityManagerFactory") public EntityManagerFactory readingEntityManagerFactory() { LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean(); em.setPersistenceUnitName("persistence.reading"); em.setDataSource(dataSource()); em.setPackagesToScan("com.company"); em.setJpaVendorAdapter(new HibernateJpaVendorAdapter()); em.afterPropertiesSet(); return em.getObject(); }
JpaTransactionManager 也配置错误.它应该是这样的:
Also the JpaTransactionManager is miss-configured too. It should be something like:
@Bean(name = "readingTransactionManager") public PlatformTransactionManager readingTransactionManager(){ JpaTransactionManager transactionManager = new JpaTransactionManager(); transactionManager.setEntityManagerFactory(readingEntityManagerFactory()); return transactionManager; }
您需要对 EntityManager 的读取和写入配置执行相同的操作.
You need to do the same for both the reading and the writing EntityManager configurations.